python报错name 'pickle' is not defined，试了一些方法仍未解决

神经网络，要求完成推理过程并得到测试数据集识别结果

相关代码及报错内容，如下

NameError                                 Traceback (most recent call last)
<ipython-input-11-9b3e3d5b2dd6> in <module>()
      1 x,t = get_data()
----> 2 network = init_network()
      3 accuracy_cnt = 0
      4 for i in range(len(x)):
      5     y = predice(network, x[i])

<ipython-input-8-a253d960dda4> in init_network()
      5 def init_network():
      6     with open("sample_weight.pkl",'rb') as f:
----> 7         network = pickle.load(f)
      8     return network
      9 

NameError: name 'pickle' is not defined

这报错是啥意思啊？该怎么解决呢？代码是发的，不会有错，可是为什么我运行不了？求解，谢谢！

代码上面加入import pickle